(This should be) paid work for social workers. They can be accompanied by someone with a medical background, like a nurse. Perfect for graduates of social sciences. (Pay them) a proper salary for motivation, too.
How about Pioneer Generation ambassadors? Looks better than police knocking on your door.
The police have lots of more important tasks on hand. How about getting a few volunteers
in every block to do visits? I don't mind being a volunteer for my block.
Get seniors to befriend seniors and keep a lookout for one another. That's the best way.